Photodynamic and photothermal therapy-driven synergistic cancer treatment assisted by zeolitic imidazolate framework-8: A review

Photodynamic therapy (PDT) and photothermal therapy (PTT) are emerging cancer treatments that induce tumor cell death by generating cytotoxic reactive oxygen species (ROS) under light or by increasing the temperature. However, the tumor microenvironment (TME) is very complex and influenced by the degree of penetration of the excitation light, and the clinical treatment efficiency of PDT and PTT is low. The combination of PDT and PTT with other immunotherapies has emerged as a promising treatment strategy. Zeolitic imidazolate framework-8 (ZIF-8) is a novel porous organofluoride material with a large specific surface area, good thermal and chemical stabilities, high drug loading capability, and pH-responsive biodegradability compared to other nanomaterials. These ZIF-8 properties have great potential in PDT and PTT, as well as in cancer synergistic treatment. Moreover, ZIF-8 is an effective protective carrier for anticancer materials. In this paper, the synthesis strategy for ZIF-8 as a carrier and functionalized material for cancer therapy is reviewed, as well as the applicable PDT and PTT principles. Additionally, a comprehensive overview of the significant effects of ZIF-8 in cancer treatment using PDT and PTT-driven systems is provided. Lastly, the challenges facing the application of ZIF-8 in this field is presented to clarify future developments.